Surgical drapes are used to perform the dual function of covering the patient and creating a barrier between the anesthetist and the surgical area. The screen portion of the surgical drape is typically attached to, and supported by, an anesthetist's arch or stand which extends transversely across and above the operating table. The portion of the surgical drape covering the patient is intended to hang down along the sides and foot portion of the operating table, while the screen or drape portion ideally extends beyond the side edges of the operating table.
The transition between the body portion of the surgical drape and the screen or drape portion must be configured to accommodate surgery performed proximate the screen or drape, such as operations performed on the upper chest region. One attempt to construct a surgical drape with a smooth transition between the screen and body portion of the drape is disclosed in U.S. Pat. No. 4,889,136 issued to Hanssen on Dec. 26, 1989. As illustrated in FIG. 3 of Hanssen, two material webs, A' and B', are advanced to two clipping and punching devices 12 and 13. The clipping device 12 forms a cut 14 through the material web B' in a direction perpendicular to the feeding direction. The clipping device 13 is constructed to cut out a piece 15 in the shape of an isosceles trapezoid with cut lines 15.sub.1 -15.sub.4 from both of the webs A' and B'. Consequently, the piece 15 in both the webs A' and B' constitutes waste. In an alternate embodiment, the clipping device 13 is arranged to cut the piece 15 solely along the cut lines 15.sub.2 -15.sub.4, so that only the piece 15 from the top web B' constitutes the waste material.
Depending on the dimensions of the surgical drape, the piece 15 can constitute approximately 0.85 sq. meters (one square yard) of material used in constructing the surgical drape. In the embodiment in which a piece 15 is cut from both the webs A' and B', the waste can constitute approximately 1.7 sq. meters (two square yards) of material, or approximately 20% of the total material used to construct the surgical drape.
It has been found that, in some applications, it is useful for the body portion of the surgical drape to cover either to the surgical table or to the feet of the patient. However, forming the necessary fitted portions to achieve this result requires additional assembly steps and increased cost and material, which is inconsistent with the high volume/low margin nature of surgical drapes.